PEX Is Popular For A Reason
PEX is widely used because it is easy to route, relatively low cost, lightweight and fast. Approved PEX systems can be suitable for drinking-water installations when correctly specified and installed.
That should be acknowledged. A credible comparison does not pretend PEX has no place.
But PEX has trade-offs:
- the internal water-contact surface is plastic
- thermal expansion is much higher than metals
- fitting systems are usually proprietary
- concealed joints still need trust
- sharp bends can kink
- long-term perception around plastic drinking-water contact is changing
The Ridgeline Difference
Ridgeline gives installers many of the routing benefits that made PEX attractive, but changes the material in contact with water.
The tube is corrugated 316L stainless steel. The outer PE cover sits outside the tube and does not touch the water. Internally, the water path is stainless steel.
That means:
- no plastic surface in contact with drinking water
- a corrosion-resistant metal water path
- flexible routing
- long runs from coils
- fewer fittings behind walls
- lower thermal movement than plastic pipework
Drinking-Water Contact
The Drinking Water Inspectorate explains that materials and fittings used in drinking-water systems must comply with water fitting requirements. For many non-metallic materials, BS 6920 testing is used to assess effects on water quality, including odour, flavour, appearance, microbial growth and extraction of substances.
PEX systems can be approved. Ridgeline is not arguing that all approved plastic is non-compliant.
The point is simpler:
If the buyer wants to avoid plastic in contact with drinking water, Ridgeline gives that route.
Microplastics: The Careful Position
Do not overstate this. WHO has reviewed microplastics in drinking-water and identified knowledge gaps and the need for more research. The responsible claim is not "PEX is unsafe".
The responsible claim is:
Ridgeline has no internal plastic water-contact surface, so it removes plastic pipe material from the water path entirely.
That is a material-design advantage, especially for homeowners, specifiers and developers who are thinking beyond minimum compliance.
Installation Comparison
| Question | PEX | Ridgeline 316L stainless |
|---|---|---|
| Flexible routing | Yes | Yes |
| Internal water-contact material | Plastic | 316L stainless steel |
| Hidden fittings | Can be reduced, but fittings still exist at branches and transitions | Can be significantly reduced with long continuous runs |
| Thermal expansion | High | Similar metal-family behaviour, with corrugation absorbing movement |
| Kink resistance | Depends on bend radius and handling | Corrugated stainless geometry resists kinking |
| System dependency | Often proprietary fittings/tools | Ridgeline fitting systems |
| Material perception | Plastic | Premium stainless steel |
Where PEX Still Makes Sense
PEX can still make sense for:
- low-cost domestic jobs
- fast installation where plastic is accepted
- familiar installer systems
- simple renovations where the rest of the property already uses plastic pipe
Where Ridgeline Makes More Sense
Ridgeline makes more sense where:
- the water path matters
- hidden joints should be minimised
- the client wants a premium pipe material
- heat pump flow and return runs need long, flexible routing
- specifiers want strong corrosion-resistance messaging
- the system needs to feel future-facing rather than lowest-cost
FAQs
Approved PEX systems are widely used for drinking-water applications. The question is whether the project is comfortable with a plastic internal water-contact surface or wants a metal water path.
Ridgeline tube has an external PE cover, but the drinking water flows inside the 316L stainless steel tube. The PE cover does not touch the water.
Rigid stainless pipe can be harder. Ridgeline is different because it is corrugated stainless steel supplied in coils, so it routes flexibly through building spaces.
Often yes, especially on long routes with multiple direction changes. Many bends that would need fittings in other systems can be formed in the tube itself.